Question

A scientific statement that describes an observation but does not explain the observation is

Answer 1

Theory stems out of an idea which is usually formulated by mathematics formalism to explain a phenomenon that cannot be explained by the obvious.
Thus a theory may work mathematically but may not represent Reality.When a theory is unproved to represent reality it is just a conjecture.
Thus there is a difference between theories and Laws of Nature.
The difficulty in theories is trying to explain things which are unexplainable with terms which have no real definition in terms of other terms which don't have a concrete definition.
Example; We have the theory of special relativity that assumes the speed of light is the same everywhere in the Universe ,but does not exactly explicate what is the actual nature and structure of light.
Quantum mechanics tries to explain light in terms of photons as being a masseless entity. Yet Einstein describe Energy as the product of a mass and the speed of light square. Hence Einstein indicated that No energy exists without a mass.

Consequently, Einstein relativity theory did not agree with Quantum mechanics. Thus we are at odds about determining which of the two theories represent reality. Is reality probabilistic or it deterministic.
Hence Einstein was at war with Niels Bohr and Heisenberg uncertainty principle, when he stated" Die Alte"(our Creator) does not play dice."
Never the less quantum mechanics is still theory And relativity of Einstein is still theory also. None of the two theories became law etched in stone.

Basically the answer to the homework question would have to be all of the above.And theories are like ghosts, they appear and disappear.Till a better ghost appears..