What does it mean to be as fragile as a house of cards?
a. easily destroyed or spoilt (This igloo is as fragile as a house of cards; I want to leave before it collapses!)
b. very soft (The cover of my new book is as soft as velvet)
c. very soft or gentle (The singer's sweet voice sounded as soft as silk)
d. very thin (This path is as thin as a rail)