Mark the correct graph that represents the type of selection that this population is likely to undergo.

Study the characteristic of a population represented in the graph below:

Which type of selection, this population is likely to undergo?

Following table shows data on amino acid substitution in the $\alpha$ chain of haemoglobin in four different mammalian species A, B, C and D. On the basis of the data shown in the table, choose the most appropriate evolutionary tree from those given below.

In a long term experiment on a population of Drosophila melanogaster, the frequency of two alleles 'a' and 'b' of a multi-allelic locus X over time has been shown in the following graph.

6 students were asked to evaluate the observed pattern and their inferences are given below.

Student 1: Environment is not uniformly selective.

Student 2: Population may be under artificial selection.

Student 3: Genetic variability is progressively reduced.

Student 4: Genetic variability is progressively increased.

Student 5: Mechanism such as genetic drift is operating from time to time.

Student 6: Selection is favouring a particular genotype through directional selection.

The appropriate conclusions were drawn by

**Formatting error resolved. Scientific name was changed in Italics.**