Right answer:
C. tan
We often use adjectives to compare things, people, events, ideas, among others. This is used to compare nouns in three ways, comparisons of equality, comparisons of inequality, and in superlatives. Here we use the comparison of equality just as tan ... como that conveys the idea of as … as. This is used when referring that two nouns are equal to one another. So here we use it with this formula:
tan + adjective/adverb + como, which is called tan comparisons and is used to compare two nouns using an adjective or adverb. The adjective in this sentence is comfortable (cómoda) and the two nouns are la ropa tradicional (the traditional clothes) and la ropa moderna (modern clothes).Therefore:
Carla: ¿Te gusta la ropa tradicional?
Daniela: Sí, me gusta mucho y es tan cómoda como la ropa