The correct answer would be D.
After many generations, only those with genes suitable to live in harsh environments can live. These genes are passed onto their offspring and then we see a rise in antibiotic resistant strains of bacteria such as Methicillin Resistant Staphylococcus Aureus (MRSA).
I'm going to use the letter W for this
Going by the question, white is the dominant trait.
WW = white
Ww = speckled
ww = black
4 chickens would be speckled because 50% of the punnet square is Ww
Answer:
C. 1.23 g/ml
Explanation:

Mass of rock = 80g
Volume of rock = final fluid volume - initial fluid volume
Volume of rock = 265 cm³ - 200 cm³ = 65 cm³


1 cm³ = 1 ml
Therefore, density of the object = 1.23 g/ml