How the four pics resembles alphabet. Can anyone explain? I can only see there is just some Greek letters like omega and pi and one soup picture?
I can't see much logic here, but as the puzzle is Greek:
Letter (Pi - $\pi$), Letter (Omega - $\Omega$), Alpha-Omega (English A-Z), Greek Alphabet Soup, put all four together - ALPHABET. A bit weak maybe?
The four pictures have one common theme:
Starting in the upper left corner, going clockwise, we have
1. the Greek letter $\pi$
2. the Greek letter $\Omega$
3. alphabet soup
4. the Greek letters $A$ (alpha) and $\Omega$
You almost answered your own question yourself... In the first picture you see Pi, which is the greek letter equivalent to the English P; in the second, you see Omega, which is the last letter of the Greek alphabet, and is pronounced similarly to a long "o"; in the third, you see an A and an Omega, which belong respectively to the modern English alphabet and the Greek alphabet; and lastly, you have a spoonful of letter soup.
The Pie is the alphabet (letter P in Greek) The Omega is the letter (O) in Greek A and Omega are both from alphabet (A from Latin and Omega is O in Greek alphabet) The bowl contains alphabet which is Alphabet cereal stock (google it)