For the Reaction X + Y $\rarr$ Z, the Reaction Rate Is Found to Depend Only Upon

For the reaction X + Y $\rarr$ Z, the reaction rate is found to depend only upon the concentration of X. A plot of 1/X verses time gives a straight line.
What is the rate law for this reaction?

A) rate = k [X]
B) rate = k [X]²
C) rate = k [X][Y]
D) rate = k [X]²[Y]