Pearl is secreted around the

Options

A. Mantle layer
B. Foreign particle between prismatic and nacreous layer
C. Foreign particle between mantle and nacreous layer
D. The shell

Answer

C

Explanation

When a foreign material such as a sand grain or a parasite happens to enter the body it adheres with the mantle. The mantle epithelium at once grows over the material in the form of a sac and enclose it. This mantle epithelium starts secreting concentric layer of nacre around the foreign material. The completed structure is called pearl.