Step 1: A quick way through this question is to look specifically for any statement that swaps two related surveying terms, since that is a common trick in these definition questions.
Step 2: Look at (C): it talks about "the first staff reading taken after setting up the instrument." Think about what actually happens on site: the very first reading after setting up over a new instrument position is always taken on a point of known elevation to fix the height of the instrument, and that reading is called a backsight, not a foresight. The statement has the two terms swapped, so (C) fails.
Step 3: Look at (E): a change point is where the surveyor closes one instrument setup and opens the next. The last reading before moving is a foresight, and the first reading after moving is a backsight. There is no intermediate sight involved at a change point at all, since intermediate sights are only the readings taken on points between the backsight and foresight within a single setup. The statement's use of "intermediate sight" is the wrong term, so (E) fails too.
Step 4: With (C) and (E) eliminated, only (A), (B) and (D) remain, and checking them against ordinary levelling vocabulary, the datum in (A), the line of collimation in (B), and the height of instrument in (D) are all textbook-accurate as written.
Step 5: That combination of surviving statements matches only one listed choice.\[\boxed{\text{Option 1: (A), (B) and (D) only}}\]