What is the number four billion, six hundred thousand, and fifty written in expanded form?

• A.  4,000,000,000 + 600,000 + 50
• B.  4,000,000,000 + 60,000 + 50
• C.  4,000,000,000 + 650,000
• D.  4, 00,000 + 6,000 + 50