Would you mind . . . . . . . . the suitcase, Sir? A. open B. opening C. opened D. to open

The correct answer is: A. open

The sentence is in the present tense, so the verb should be in the infinitive form. The other options are either past participles or gerunds, which are not appropriate in this context.

• Opening is a gerund, which is a verb form that is used as a noun. It cannot be used as the main verb of a sentence.
• Opened is a past participle, which is used to form the perfect tenses and the passive voice. It cannot be used as the main verb of a sentence.
• To open is the infinitive form of the verb, which is used to express a purpose or intention. It is the correct answer in this context.

Here is a rewritten version of the sentence:

Would you mind opening the suitcase, Sir?