In Which of the Following Situations Is a Search Warrant

In which of the following situations is a search warrant required?

A) To use a telescope to peer through the suspect's widow and view marijuana plants growing inside his home while standing in an open field.
B) To fly a helicopter over the suspect's backyard, which is shielded from ground-level view by a high fence, and take pictures of his marijuana garden.
C) To aim a thermal-imaging device at a suspect's home from a vantage point outside the curtilage to detect heat distribution patterns inside the home.
D) All of them.