Which method produces a simple random sample of the population consisting of a day's production of $1000$ network routers?

Use the first $25$ routers completed after arrival of the quality engineer.

Put the serial numbers $0001,0002,$dots,$1000$ on ping$-$pong balls, shake them, and draw out $25.$

Use the $25$ routers with serial numbers $0040,0080,0120,$dots,$1000.$

Use the $25$ routers produced between $10$:$00$ a$.$m$.$ and $11$:$00$ a$.$m$.$