What is a characteristic of DDR SDRAM?

What is a characteristic of DDR SDRAM?

• It transfers data twice per clock cycle compared to once per clock cycle for SDRAM.
• DDR SDRAM modules have double the number of pins of SDRAM memory modules.
• It is dynamic memory whereas SDRAM is static memory.
• It operates at double the voltage of SDRAM memory.
  

  Explanation: DDR SDRAM transfers data twice per clock cycle, whereas SDRAM transfers data once each clock cycle. Both DDR SDRAM and SDRAM are forms of dynamic memory. The difference in data transfer rate between DDR SDRAM and SDRAM is not determined by the number of pins, nor the operating voltage.