Correct option is D
f is given continuous f maps compact set to compact set.
Furthermore, range is given (0,1) (0,1) So ,
the image of fff must be uncountable, as a compact subset of a metric space like
(0,1)×(0,1)(0,1) \times (0,1)(0,1)×(0,1) that is nontrivial must be uncountable.
The function fff is continuous, and the domain [0,1]×[0,1][0,1] \times [0,1][0,1]×[0,1] is path-connected.
The continuous image of a path-connected set is also path-connected.
Therefore, the image of fff is path-connected.
as all statements given in Option A,B and C are true. Option D must be correct.
Also , From given conditions f need not have empty interior.