Consider the following minerals:<br/>1. Calcium<br/>2. Iron<br/>3. Sodium<br/><br/>Which of the minerals given above is/are required by human body for the contraction of muscles?

1. Calcium — Calcium ions are essential for muscle contraction; they enable interaction between actin and myosin in muscle fibers. Verdict: Correct.

2. Iron — Iron is mainly known for hemoglobin and oxygen transport, but it is also present in myoglobin and several enzymes that support muscle metabolism and contraction. Verdict: Correct.

3. Sodium — Sodium is crucial for generation and transmission of nerve impulses that trigger muscle contraction, and also helps in muscle function. Verdict: Correct.

Since all three minerals are required for proper muscle contraction/function, the correct answer is (d) 1, 2 and 3.