Final answer:
Approximately 2,200 years passed between the Sumerian invention of writing around 3000 BCE and the Greek adoption of an alphabet around 800 - 750 BCE, which makes the correct answer (a) Approximately 2,000 years.
Step-by-step explanation:
Time Between Sumerian Writing and Greek Alphabet
The invention of writing by the Sumerians, characterized by the cuneiform script, dates back to around 3000 BCE. Cuneiform is one of the earliest known writings, initially used for keeping tax records but evolved into a complex system used for a variety of administrative and literary purposes. On the other hand, the ancient Greeks adopted an alphabet influenced by the Phoenician writing system around the 8th century BCE, between 800 - 750 BCE. The Greeks adapted this to record their own language and literature.
Given these dates, the period between the Sumerians' development of cuneiform and the Greek adoption of an alphabet is approximately 2,200 years. Therefore, the Greek adoption of an alphabet happened roughly 2,000 years after the invention of writing by the Sumerians.
Thus, the correct answer is (a) Approximately 2,000 years.