Answer:
a) less than Mercury's.
Explanation:
For orbital time period  of a planet  , the expression is
T² = 4Ď² RÂł / GM
T is time period , R is radius of orbit , G is universal gravitational constant , M is mass of the star or sun
T² â RÂł
As radius of orbit increases , time period increases . The given planet is making around a star whose mass is equal that  of  sun so M is same as sun .
The given planet has time period equal to .01 years which is less than that of Mercury and Venus , hence its R will be less than orbit of both of them or less than mercury's .