Final answer:
The aspect of sign that distinguishes how you sign numbers 1-5 from how you sign numbers 6-10 is handshape.
Step-by-step explanation:
The aspect of sign that distinguishes how you sign numbers 1-5 from how you sign numbers 6-10 is a) Handshape. When signing numbers 1-5, the handshape changes from the palm backward position to the palm forward position. However, when signing numbers 6-10, the handshape changes from the palm forward position to the palm backward position.