Final answer:
True, regioselectivity involves the preferential formation of one isomer over another in chemical reactions where more than one outcome is possible, due to differences in intermediate stability.
Step-by-step explanation:
True or false: regioselectivity is the addition in a preferred location/arrangement when more than one possibility is available. This statement is true. Regioselectivity refers to the phenomenon during chemical reactions, specifically electrophilic additions, where two constitutional isomers are possible outcomes. However, one isomer is formed either exclusively or predominantly due to the unequal stability of potential intermediates, such as carbocations. This selective process results in a major product and potentially a minor product, but with a clear preference for the formation of one over the other.