The correct answer is "... Although my French windows face towards Ottershaw and the blind was up... I saw nothing of it."
The quotation clearly states that both the object (Ottershaw) and the narrator are in opposite sides of a window, which lies between them.
The other options cannot be correct since:
In the second quotation, the object is the night sky, and its location can be considered to be up. However, the location from which the narrator observes the object is unclear.
In the third quotation, the identity of the object itself is unclear, defining it as this strangest of all things. Nevertheless, its location is set as the earth, and outer space as the place of provinence. The narrator states its location to be "there", which creates an ambiguity issue - not specifying the location to be the earth or outer space.