The colourless plastids are called as……………….and their main function is …………….(a) Chloroplasts, photosynthesis(b) Leucoplasts, respiration(c) Chromoplasts, protection from sunlight(d) Leucoplasts, storage of food

The correct answer is:

(d) Leucoplasts, storage of food

Explanation:
Plastids are double-membrane organelles found in plant cells and some protists. Based on their functions and pigments, plastids are categorized into three types: chloroplasts, chromoplasts, and leucoplasts.

Chloroplasts are green plastids containing chlorophyll and are responsible for photosynthesis.
Chromoplasts are colored plastids (other than green) that provide pigmentation to flowers, fruits, and other plant parts.
Leucoplasts are colorless plastids that are primarily involved in storage.
Leucoplasts store starch, lipids, or proteins depending on the cell's requirements. Subtypes of leucoplasts include:

Amyloplasts for starch storage.
Elaioplasts for lipid storage.
Proteinoplasts for protein storage.
Hence, the correct option is (d) Leucoplasts, storage of food.