Explanation:

- IBM 7094 series:

- Part of the IBM 7000 series, known for scientific computing.

- Used transistors, indicating it was part of second-generation computers.

- IBM 1400 series:

- Also relied on transistors.

- Designed for business data processing, making it part of second-generation computers.

- CDC 164:

- Built by Control Data Corporation.

- Utilized transistor technology indicative of second-generation computers.

- Answer: All

- All three listed options are indeed second-generation computers, which used transistors instead of vacuum tubes.