Question

This is really confusing. Thanks for helping.

Answer 1

Count change of signs to tell positive roots
then replace x with -x and evaluate, then count change in sign for negative roots


initially
+, -, -, +, +, -
3 changes
3 or 1 positive roots


replacing x with -x
-,-,+,+,-,-
2 changes
2 or 0 negative roots



B is answer