What comes next in the sequence: 2, 6, 12, 20, 30, ____?

Step 1: በተከታታይ ቁጥሮች መካከል ያለውን ልዩነት እንፈልግ። The differences between consecutive terms are: $6 - 2 = 4$ $12 - 6 = 6$ $20 - 12 = 8$ $30 - 20 = 10$

Step 2: የልዩነቶቹን ቅደም ተከተል እንመርምር። The differences form a sequence: 4, 6, 8, 10. This is an arithmetic progression where each term increases by 2.

Step 3: ቀጣዩን ልዩነት እንፈልግ። Following this pattern, the next difference should be: $10 + 2 = 12$

Step 4: በተከታታይ ውስጥ ያለውን ቀጣይ ቁጥር እንፈልግ። To find the next number in the original sequence, add this difference to the last term (30): $30 + 12 = 42$

ስለዚህ, ቀጣዩ ቁጥር 42 ነው። ይህ ደግሞ አማራጭ C) ነው።

The next number in the sequence is $\boxed{42}$. The correct option is C).