According to the Neo-Darwinian theory,which of the following is responsible for the origin of new species?

When glucose reacts with bromine water,the main product is:

From the top of a hill $h$ metres high,the angles of depression of the top and the bottom of a pillar are $\alpha$ and $\beta$ respectively. The height (in metres) of the pillar is

If $\sin ^{-1} x - \cos ^{-1} x = \frac{\pi}{6}$,then $x$ is equal to

Dividing the interval $[0,6]$ into $6$ equal parts and by using the trapezoidal rule,the value of $\int_0^6 x^3 dx$ is approximately:

An electron (mass = $9.1 \times 10^{-31} \ kg$; charge = $1.6 \times 10^{-19} \ C$) experiences no deflection if subjected to an electric field of $3.2 \times 10^5 \ V/m$ and a magnetic field of $2.0 \times 10^{-3} \ Wb/m^2$. Both the fields are normal to the path of the electron and to each other. If the electric field is removed,then the electron will revolve in an orbit of radius.......$m$