The following statement is true when it comes to numbering the carbon atoms in a hydrocarbon:

(a) You can number them any way you want as long as you are consistent.

(b) You must number them from left to right since that is the direction we normally read.

(c) You must make sure that the any multiple bonds end up with the highest number of positions possible.

(d) You must make sure that any multiple bonds end up with the lowest number of positions possible.