The correct substitutes would be " A. Ellos lo compraron
In English, Ellos compraron El Reloj Pulsera means : They (masculine) bought the watch
Reloj : Masculine singular Pronoun, which means that the objective pronoun should be : LO
Hope this helps
In the ovule. When the 'pollen', which are the sperm of a flower, reach the stigma, the 'pollen' will roll down through the style to the ovary.
Every adenine base is paired to a thymine base, so there have to 500 thymine bases to match up with the adenine bases.
Answer: temporal reproductive isolation
Explanation:
In temporal reproductive isolation the individuals of same or different species do not mate due to the fact that they remain active at different times of the day or different seasons for mating and reproduction.
The two species of toads are showing temporal reproductive isolation as they have different mating seasons that is summer and fall. Although they were induced to mate in the laboratory conditions but they remain isolated in nature.