Mollusks grow shell during the

A mollusk's mantle (skin) releases liquid shell materials, which harden on contact with water or air. Gastropod and nautilus shells grow from their outermost edge. As the mollusk grows, its shell develops more whorls (single turns in a spiral shell) or chambers

the answer is neither ball has a charge.

because if they were both positively charged, they will repel each other.

if they were positively and negatively charged, they will seek.