Which of the following is true of reproduction in a pine tree? A. The zygote grows into an embryo. B. The pollen tube contains two diploid sperm. C. Both sperm fertilize the egg. D. The cones are diploid.

The answer to the question given is letter D. The cones are diploid.

The true reproduction in a pine tree is its cones which are diploid. Conifers has both male and female cones. Once the ovule is fertilized, a diploid sporophyte is produced, which gives rise to the embryo.