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Number theory Difficulty 1.0 Junior Find the answer United Kingdom

How many of the following statements are true?

A prime multiplied by a prime is always a prime.
A square multiplied by a square is always a square.
An odd number multiplied by an odd number is always an odd number.
An even number multiplied by an even number is always an even number.

(A) $0$ (B) $1$ (C) $2$ (D) $3$ (E) $4$

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Source: UK Mathematics Trust, licensed © UK Mathematics Trust; past papers published free at ukmt.org.uk. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.