The students had no choice … to do as they had been commanded.

Analyze the question The sentence is: "The students had no choice __ to do as they had been commanded." We need a word that links "no choice" to "to do as they were commanded," meaning "no choice other than to do it."

Explain the concept In English, "but" can work as a preposition meaning "except." The structure "no choice but to + verb" is a fixed idiom. Examples:

• "She had no choice but to leave."
• "We had no option but to wait."

"Except" also means "other than," but it does not fit this idiom. We say "no choice but to," not "no choice except to." "Except to" is not the standard idiomatic form, although some speakers use it loosely. Exam setters test the idiom "no choice but to."

Check each option

• A. except: Close in meaning, but not the standard collocation with "no choice... to."
• B. but: Correct. "No choice but to do" is the established idiom.
• C. rather: "No choice rather to do" is ungrammatical. "Rather than" is a different structure.
• D. even: "No choice even to do" makes no sense here.

Answer The correct option is B. but.

The sentence reads: "The students had no choice but to do as they had been commanded."

Tip Memorize these fixed phrases: "no choice but to," "no option but to," "no alternative but to," and "cannot but + verb." In each, "but" means "except." If you see "no choice/option/alternative" followed by a blank and "to," think but.