Phenotypes:

a: can be subject to environmental conditions.
b: only result from gene transcription.
c: are always expressed in the same way.
d: always result solely from the actions of a single gene.
e: none of the answer options is correct.

A: can be subject to environmental conditions.

Explanation:

Phenotype is a genetics term used to describe an individual's observable characteristics that result from interactions with the genotype and nonheritable environmental factors.

Phenotypes are the manifested aspects of the morphology, physiology, biochemical properties, behavior and ecological relationships of an organism.

Given these statements, it can be concluded that two organisms cannot have the same phenotype (not even twins), because there will always be, however small, a morphological or physiological difference between them.

the truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey.

the answer is "a.) well–developed vascular system."

explanation: