Natural Source Food Ltd. has developed a line of biscuits sweetened exclusively with organic honey. Although Natural Source Food is selling these products online, they must be sold in retail outlets to gain economies of scale. The main barrier to entry Natural Food is likely to encounter here is:

a. Consumers' switching costs.

b. Government licensing and permits.

c. Access to distribution channels.

d. High threats from substitutes.

e. Cost disadvantages independent of economies of scale.