Cassandra is asked to identify a solution in her laboratory classroom as acidic, basic, or neutral. She is given litmus
paper as an indicator. Once placed in the solution, the red litmus paper turns blue,
What result can Cassandra expect when she tests the solution with the blue litmus paper?
The blue litmus paper will turn
The solution is

Blue litmus paper remains blue

Solution is basic

Explanation:

Blue litmus paper turns red when a solution is acidic while the red litmus paper turns blue when a solution is alkaline.  In this case, Cassandra observed that red litmus paper turned blue, a clear indicator that the solution is alkaline. Similarly, when using blue litmus paper, the color remains blue for the same solution since it's basic.

option number c is the right answer.

at right angles to each other