Question

which type of traits vary quantitatively due to the interaction of multiple genes?
○ polygenic
○ codominant
○ incomplete dominant
○ dominant

Explanation:

To solve this, we analyze each option:

• Polygenic traits are controlled by multiple genes (poly = many, genic = related to genes) and show quantitative variation (e.g., height, skin color).
• Codominant traits involve both alleles being expressed equally (e.g., AB blood type), not quantitative variation from multiple genes.
• Incomplete dominant traits show a blend of alleles (e.g., pink flowers from red and white), not due to multiple genes for quantitative variation.
• Dominant traits are controlled by one (or a few) genes where one allele masks another, not multiple genes for quantitative variation.

So the correct option is the one related to multiple genes causing quantitative variation.

Answer:

A. polygenic