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# Pick out the chemically most reactive elements from the given triads.

- Li, Na, K
- F, CI, Br

- Li and F
- Li and Br
- K and F
- K and Br

Correct Answer: (c) K and F

Explanation: As potassium (k) and fluorine (F) reacts with most of the other elements. Hence, they are most reactive in the given triads.

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