Q1: although i do not pretend to understand the science behind it , this is reassuring to me

a. adverb
b. adjective
c. article
d. compound adjective

q2: scientific information like this does not always hold my attention

a. article
b. adjective
c. proper adjective
d. adverb

q3: however , when a science article is about something that strongly appeals to me , such as snowflakes , i became interested

a. article
b. adjective
c. proper adjective
d. adverb

q4: i sometimes read the science section of the sunday newspaper

a. article
b. adjective
c. proper adjective
d. adverb