Question

lead blocks the actions of which mineral?
a. calcium
b. copper
c. selenium
d. chromium

Explanation:

Lead can interfere with the function of calcium in the body, blocking its actions. Calcium is an essential mineral involved in many physiological processes, and lead's chemical similarity to calcium (in terms of ionic radius and some binding properties) allows it to compete for and block calcium - related pathways. Copper, selenium, and chromium have different chemical properties and binding sites, so lead does not typically block their actions.

Answer:

a. Calcium