What is the variation of traits among members of the same species called?

The theory of natural selection is based on which of the following?

The phenomenon of industrial melanism demonstrates:

Given below are two statements.
Statement $I$ - In disruptive natural selection,individuals acquire peripheral character value at both the ends of the distribution curve.
Statement $II$ - Industrial melanism is an example of disruptive selection.
In the light of the above statements,select the correct option given below:

In a species,the weight of newborn ranges from $2$ to $5 \; kg$. $97 \%$ of the newborns with an average weight between $3$ to $3.3 \; kg$ survive,whereas $99 \%$ of the infants born with weights from $2$ to $2.5 \; kg$ or $4.5$ to $5 \; kg$ die. Which type of selection process is taking place?

The sequence of events in geographic speciation is most likely to be