Topic: Pronoun (সর্বনাম),

Best Answer Explained in Below-:

The sentence "We got into a bus ---- was full of people." requires a relative pronoun to connect the main clause to additional information about "the bus." In this context, the relative pronoun must refer back to the noun "bus" and provide necessary details about it.

Let’s examine the options:

A) "who" typically refers to people, not objects. Since "bus" is an inanimate object, using "who" would be grammatically incorrect.

B) "which" is the correct choice here. It is used to refer to things and provides non-essential (or essential) information about the noun. In this case, "which" effectively links the clause to the noun, indicating that the bus we entered was occupied by many people.

C) "and" serves as a conjunction, which does not fit in this context since we are not connecting two independent clauses.

D) "what" is typically used to inquire or refer to things in a more indefinite manner, making it unsuitable for this specific reference to "bus."

Therefore, "which" effectively completes the sentence because it correctly links the description to the noun "bus" in a way that clarifies the statement without altering its meaning.