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Number theory Difficulty 2.0 Junior Find the answer United Kingdom

What is the remainder when $2^2 \times 3^3 \times 5^5 \times 7^7$ is divided by 8?

(A) $2$ (B) $3$ (C) $4$ (D) $5$ (E) $7$

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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.