Feather color in budgies is determined by two different genes, Y and B, one for pigment onthe outside and one for the inside of the feather. YYBB, YyBB, or YYBb is green; yyBB or yyBbisblue; YYbb or Yybb is yellow; and yybb is white. A blue budgie is crossed with a white budgie. Which of the following results is NOT possible?

A) green offspring only

B) yellow offspring only

C) blue offspring only

D) green and yellow offspring

Therefore, the following results are not possible:

A) green offspring only

B) yellow offspring only

D) green and yellow offspring.

Step-by-step explanation:

We know that feather color in budgies is determined by two different genes. For blue color are combinations yyBB or yyBb. For white color is combination yybb.

By combining these two colors we can not get green and yellow.

Because green and yellow colors are in this form:

Green: YYBB, YyBB, or YYBb

Yellow: YYbb or Yybb.

Therefore, the following results are not possible:

A) green offspring only

B) yellow offspring only

D) green and yellow offspring.