Which of the following are contraindications for sealants?

1 . Teeth with shallow open grooves
2 . Occlusal pits and fissures of non-carious primary teeth
3 . Teeth with well-coalesced pits and fissures
4 . Teeth that have been caries-free for 4 or more years
a. 1, 2, 3, 4
b. 1, 3, 4
c. 1, 2
d. 1, 2, 3

b
RATIONALE: The following are contraindications for sealants: - Teeth with shallow open grooves - Teeth with well-coalesced pits and fissures - Teeth that have been caries-free for 4 or more years