Suppose that there is a shift in society's preferences towards "green" technologies and now more people prefer to drive electric vehicles. Further, suppose that government has decided to introduce a tax on electric car producers, the revenues of which will be used to build the infrastructure to allow public charging of electric vehicles. Indicate the changes in the electric vehicle market by shifting the demand and/or supply curves.
a) Demand curve shifts right
b) Demand curve shifts left
c) Supply curve shifts right
d) Both a and c