True breeding Drosophila flies with curved wings and dark

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True breeding Drosophila flies with curved wings and dark bodies were mated with true breeding short wings and tan body Drosophila. The F1 progeny was observed to be with curved wings and tan body. The F1 progeny was again allowed to breed and
produced flies of the following phenotype, 45 curved wings tan body, 15 short wings tan body, 16 curved wings dark body and, 6 short wings dark body.
The mode of inheritance is

1. Typical Mendelian with curved wings and tan body being dominant
2. Typical non-Mendelian with curved wings and tan body not following any pattern
3. Mendelian with suppression of phenotypes
4. Mendelian with single crossover

Correct Option: A

Let us denote the dominant curved wings allele by C, short wings by c, tan body by D, dark body by d. Assumption is made that curved wings and tan body are recessive traits and that they follow Mendelian genetics.
Now, Fsub>1 progeny CcDd (Since, Fsub>1 progeny was observed to be with curved wings and tan body)
Cross breed → CcDd X CcDd

f , progency →	C C D D / C c D d / C C D d / C c D D		c c D D / ccD d		C c d d / C C dd		ccdd
	(45)		(15)		(16)		(6)
	9	:	3	:	3.3	:	1.2

which approximately becomes 9 : 3 : 3 : 1, which is the phenotypic ratio of F₂ generation according to Mendelian genetics