Without science and the scientific spirit, we shall just drift along.

Answer: Option B

Gently : with a mild, kind, or tender manner.
Wander : walk or move in a leisurely or aimless way.
Cautiously : in a way that deliberately avoids potential problems or dangers.
Peacefully : without disturbance; tranquilly.
Drift : move passively, aimlessly, or involuntarily into a certain situation or condition.

Synonym of Drift is Wander