Question

shoes and buttons ___5___ be polished daily.

• A. have to
• B. shall
• C. will
• D. could

Answer 1

The correct option is A have to

Option A is the correct answer because 'have to' is used to express a strong obligation, when we use 'have to' this usually means that some external circumstance makes the obligation necessary.

option D is incorrect because we use 'could' to indicate that something is possibly true, or that it may possibly happen, but in this case, it is a necessity.

Option B and C are incorrect because 'will' and 'shall' are used in a future tense with no defined time limit, whereas the rule clearly states that this rule must be followed with effect immediately.