Under FIDIC 1999, both Yellow Book and Silver Book include provisions requiring the Contractor to scrutinise the Employer's Requirements, but the timing and level of responsibility differ significantly.
In the Yellow Book, Sub-Clause 5.1 allows the Contractor to review the Employer's Requirements and, after contract award, notify errors, ambiguities, or inconsistencies. The risk remains more balanced, and the Contractor may rely on the Employer's Requirements to a reasonable extent.
In contrast, the Silver Book (EPC/Turnkey) imposes a much stricter obligation. The Contractor is deemed to have fully scrutinised and satisfied itself as to the correctness and sufficiency of the Employer's Requirements during the tender stage. This reflects the Silver Book's risk allocation, where the Contractor assumes greater responsibility for design and project risks, including errors in the Employer's Requirements (with limited exceptions).
Therefore, Option D correctly captures this fundamental distinction:
* Yellow Book # scrutiny mainly after contract award with notification rights.
* Silver Book # stronger pre-contract obligation during tender, with greater risk assumed by the Contractor.
This difference is a key element in FIDIC risk allocation philosophy between design-build (Yellow) and EPC
/turnkey (Silver) contracts.

Under the FIDIC Red Book 2017, Clause 21 establishes a standing Dispute Avoidance/Adjudication Board (DAAB) as a default requirement. This is a major evolution from the 1999 edition, where a Dispute Adjudication Board (DAB) could be ad hoc. Therefore, Option C is correct, as the General Conditions clearly provide for a standing DAAB appointed at the outset of the Contract.
Option D is also correct. The appointment procedure for DAAB members requires mutual agreement between the Parties. Even if one Party nominates a member, that nomination must be accepted by the other Party to ensure neutrality, independence, and confidence in the dispute resolution process.
Option A is incorrect because amicable settlement (Clause 21.5) is required after a DAAB decision and before arbitration, not before referring a matter to the DAAB.
Option B is incorrect because DAAB decisions are binding immediately (whether or not final), unless and until revised by arbitration. They are not dependent on prior confirmation by arbitration to be binding.
Option E is incorrect because failure to give a Notice of Dissatisfaction (NoD) relates to a DAAB decision becoming final and binding-not an Engineer's determination. The statement incorrectly mixes procedural steps.
These provisions reflect FIDIC's structured multi-tier dispute resolution system, promoting early resolution through DAAB before escalation to arbitration.

The Employer must provide detailed notice to the Contractor regarding intended changes material to financial arrangements, enabling transparency and allowing the Contractor to assess impacts and prepare claims or adjustments accordingly.
This obligation supports fair risk allocation and project control.
References:
FIDIC Red, Yellow, Silver Books 1999 & 2017 Editions - Various clauses on Notices and Variations FIDIC Contract Manager Study Guide, Module on Communication and Financial Notices

Under the FIDIC Red Book and Yellow Book, 1999 editions, the Engineer issues Interim Payment Certificates certifying the amounts due to the Contractor for completed works and materials on site (Sub- Clause 14.6). The Employer is generally bound by the Payment Certificate and must pay accordingly, except where there is a lawful set-off or compensation claim against the Contractor.
Option A is correct because the Employer must pay the amount certified except for compensation claims that may be offset against the payment (Sub-Clause 14.6).
Option D is also correct: If the Employer intends to claim against the Contractor (e.g., for damages or defects), it must notify the Contractor under Sub-Clause 2.5 and provide particulars. The Engineer then assesses and decides on the claim and incorporates any agreed deductions into the Payment Certificate.
Option B is incorrect because the Employer is indeed bound by the Payment Certificate unless lawful deductions or disputes arise.
Option C is incorrect as the Employer can withhold amounts due for compensation claims once these are properly notified and substantiated.
References:
FIDIC Red and Yellow Books, 1999 Edition, Sub-Clause 14.6 - Interim Payments FIDIC Red and Yellow Books, 1999 Edition, Sub-Clause 2.5 - Employer's Claims FIDIC Contract Manager Study Guide, Module on Payment Procedures and Financial Management

Under the FIDIC Red Book 1999, discharge becomes effective when the Contractor has received full payment certified by the Final Payment Certificate and the return of the Performance Security (Sub-Clause 14.10).
Both elements must be completed for the contract to be considered fully discharged, releasing the Contractor from further obligations or liabilities under the contract.
Option A is incomplete as payment alone does not fully discharge the Contractor.
Option B is incomplete as return of Performance Security alone is insufficient.
Option D is incorrect because the contract does not require a discharge notice signed by the Employer beyond these conditions.
References:
FIDIC Red Book 1999 Edition, Sub-Clause 14.10 - Final Payment and Discharge FIDIC Contract Manager Study Guide, Module on Project Close-Out and Final Account