Consider the following table of activities A through E in which A is the start node and E is the stop node. Assume all activities require the same resource.

Activity	duration (days)	Predecessor
A	5	--
B	15	A
C	10	A
D	5	A
E	5	B, C, D

Assume the project is resource-constrained but not time-constrained. Assume only one resource is available and that resource can only do one activity at a time. Activities B, C and D all have the same early start date (time). Since there is only one resource, only one of the activities B, C, D can be started on the early start date. Which should be started first?