Which of these is/are true?
1. Trabeculae of spongy bone are covered with endoseum
2. The inner layer of the periosteum contains osteoblasts
3. Perforating (Sharpey's) fibers anchor tendons to bone
4. Diploe is hemopoietic in adults
a) 1 & 3
b) 2 & 4
c) 1, 2 & 3
d) 4 only
e) all of the above