Harold, who is driving too fast for conditions, collides with a truck carrying explosives. The truck is unmarked, so Harold has no way of knowing what it contains. The collision causes an explosion, which shatters glass in a building a block away. The glass injures Ida, who is working inside the building. John, who is walking down the street near the site of the collision, is seriously burned as a result of the explosion.

a. Harold's negligent driving is the proximate cause of Ida's injury.
b. Harold's negligent driving is the proximate cause of John's injury.
c. Both Ida and John are within the zone of danger of the collision.
d. Ida is in the zone of danger.
e. Harold's negligent driving is the legal cause of Ida's injury.