The correct answer is C.
To show Component records as a related list on Product, the app builder should create a relationship field on the child object, Component, pointing to the parent object, Product. Salesforce documentation explains that when a lookup relationship is defined, the lookup field is added on one object and a related list can be shown on the associated object's page layout.
A is unnecessary unless the requirement is many-to-many. B is incorrect because a roll-up summary does not create a related list. D is incorrect because the relationship field direction is wrong; the field should be on Component, not Product.

The correct answer is C.
A junction object is commonly created with two master-detail relationships. Salesforce documentation states that sharing access to a junction object record is determined by the user's access to both associated master records and the sharing setting on the relationship fields.
Here, Account Interest is the junction object between Account and Interest. If users do not have read access to the Interest object, they cannot view the Interest records. Because access to the junction object depends on access to both master records, they also cannot view the associated Account Interest records.
Why not others:
A is wrong because lack of read access to Interest does not give read-only access automatically.
B is wrong because the user can still view the Account if they have Account access.
D is wrong because junction object access is not simply "show junction but hide Interest details."

The correct answer is B. User will be presented with a "Record Lock" notification.
When a record is submitted for approval, Salesforce locks the record to prevent users from editing it during the approval process. Salesforce documentation states that records submitted for approval are locked, and by default only admins can edit locked records unless editability settings allow otherwise.
The employee submitted the Opportunity for approval, so the employee cannot simply edit the Description field after submission. The expected user experience is a locked-record message.

The correct answer is D.
Salesforce allows converting a master-detail relationship to a lookup relationship only when there are no roll- up summary fields on the master object that summarize the detail records. Salesforce documentation states that after a roll-up summary field exists on an object, the object's master-detail relationship can't be converted into a lookup relationship.
In this case, if Account has roll-up summary fields based on related Park records, Salesforce blocks the conversion.
A is incorrect because a flow using Account does not normally prevent converting the relationship. B is incorrect because formulas on Park referencing Account are not the primary restriction. C is incorrect because custom objects do not need at least one master-detail relationship for reporting.

The correct answer is A because the rule must fire only when Sales Organization = Canada and Pricing Tier is blank.
ISPICKVAL() checks whether a picklist equals a specific text value, and TEXT() converts a picklist value into text so ISBLANK() can evaluate whether it is empty. Salesforce documents ISPICKVAL() for comparing picklist values and TEXT() for converting picklist values in formulas.
Why others are incorrect:
B has invalid formula structure.
C uses incorrect picklist blank logic.
D uses OR , which would require Pricing Tier even when Sales Organization is not Canada.