Hemitropous ovule is the one which becomes curved so that the nucellus and embryo sac lie at right angles to the funicle.

Explanation:

- An ovule is a structure present in the ovary of a flower that develops into a seed after fertilization.
- The ovule consists of a megasporangium, which contains the female gametophyte, and the integuments, which protect the female gametophyte.
- The ovule is attached to the ovary wall by means of a stalk-like structure called the funicle.
- There are four types of ovules based on the orientation of the ovule axis and the position of the micropyle (the opening in the integuments through which the pollen tube enters). They are:

1. Anatropous ovule: The ovule becomes inverted and the micropyle faces downwards. The nucellus and the embryo sac are suspended from the top of the ovule by a stalk called the funicle.

2. Campylotropous ovule: The ovule becomes curved so that the micropyle faces downwards and lies close to the funicle. The nucellus and the embryo sac are also curved.

3. Orthotropous ovule: The ovule is straight, and the micropyle is at the top. The nucellus and the embryo sac lie parallel to the funicle.

4. Hemitropous ovule: The ovule becomes curved so that the nucellus and embryo sac lie at right angles to the funicle. The micropyle is located on the curved side of the ovule.

- In the case of a hemitropous ovule, the curvature of the ovule occurs during its development, and it results in the nucellus and embryo sac being orientated at right angles to the funicle.
- The hemitropous ovule is also called a semi-anatropous ovule. It is intermediate between the anatropous and the orthotropous ovule.

Thus, the correct answer is option A, hemitropous.