#most-constrained-variable

Question 1: Single choice

Seven speakers (T, L, B, C, S, P, N) each get one of four slots, 1–4 pm. These pairs may not share a slot: every pair within {B, C, N}, within {L, P, N}, within {T, L, N}, and the pairs S–P, L–C and C–P. No speaker has a fixed slot, so all seven domains are equal. Which speaker should be assigned first to find a solution quickly?

Turing, because he comes first in the speaker list1
Socrates, who is in a single constraint2
Curie, who is in four constraints3
Newton, who is in five constraints4

#most-constrained-variable

Timed test