The correct option is
A Pacific Yew
Taxol is a new anti-cancer drug that is a natural product derived from the bark of the Pacific Yew tree. The drug promotes polymerization and stabilization of tubulin to microtubules and interferes with the mitotic spindle. It is effective in the treatment of patients with refractory ovarian cancer, breast cancer, malignant melanoma and probably other solid tumors. Therefore, the correct answer is option A.