Q. When making a polysulphide impression for a caste crown, custom trays are usually preferred over stock trays for all of the following reasons except_______________?
a. Custom trays facilitate uniform contraction of impression material
b. Custom trays require less impression material
c. Stock trays may be short in the flange area
d. Impressions made n the custom trays are easier to remove from the mouth
No explanation is available for this question!