The younger brother insisted that he should be a … to the account.

Analyze the question

The sentence is: "The younger brother insisted that he should be a .......... to the account." We need the word that fits with the preposition "to" and the noun "account" (a bank account).

Explain the concept

This is a vocabulary-in-context question that tests collocation, meaning which words naturally go together with which prepositions.

• Signatory to an account, agreement, or treaty: a person authorised to sign on it. "Signatory to the account" is a standard banking expression.
• Partner: usually takes "in" or "of" (partner in a business), not "to the account."
• Guarantor: usually "guarantor for" or "guarantor of" a loan or person.
• Participant: usually "participant in" an event or activity.

Step-by-step solution

1. The sentence is about a bank account, so we need a word describing a person's role in relation to it.
2. The preposition "to" narrows the choices. "Signatory to" is the natural collocation.
3. Meaning check: the younger brother wanted the right to sign for, and so operate, the account. This fits "signatory" perfectly.
4. The other options fail on either meaning or preposition: • partner to the account: unnatural • guarantor to the account: wrong preposition and meaning • participant to the account: unnatural, since you participate in something

Answer: B. signatory

Exam tip

In "word completion" questions, always check the preposition after the blank. Words like signatory to, participant in, guarantor for, and partner in each have fixed pairings. Learning these collocations can help you eliminate wrong options quickly.