1 – Correct
The gamete is always haploid meaning it would contain half the number of chromosomes as other body cells. Since body cells of sheep have 54 chromosomes, the gametes would contain 27 chromosomes.
2 – Correct
Stem cells are the cells which make the embryo. So stage 4 would have the same properties as stem cells.
3 – Wrong
The gamete used is produced by meiosis.
Since statements 1 and 2 are correct, E is the answer.