Question

which of the following occurs during artificial cross - pollination?
the plants reproduce sexually by self - pollination.
the scientist completely controls the transfer of pollen from one flower to the stigma of another.
a different species of plant is crossed with the original.

Explanation:

Artificial cross - pollination is a process where a scientist intervenes. In self - pollination (first option), pollen is transferred within the same flower or between flowers of the same plant without external control. For the third option, cross - pollination in artificial cross - pollination is usually within the same species (unless in very specific hybridization experiments which are not the general case of artificial cross - pollination). The key in artificial cross - pollination is the scientist's control over pollen transfer from one flower to another's stigma.

Answer:

The scientist completely controls the transfer of pollen from one flower to the stigma of another.