5. Heartwood and sapwood consist of _____.
(A) bark
(B) periderm
(C) secondary phloem
(D) secondary xylem
(E) vascular cambium
答案:登入後查看
統計: A(1), B(1), C(2), D(7), E(1) #3429684
統計: A(1), B(1), C(2), D(7), E(1) #3429684