Computers that once took up entire rooms are now……….. to put on desktops and into wristwatches.small enoughsmall enoughsmaller thanso smallas small as

The correct completion of the sentence is "small enough."

The full sentence would read: "Computers that once took up entire rooms are now small enough to put on desktops and into wristwatches."

This phrase emphasizes the tremendous advancements in technology that have led to miniaturization in computing. In the past, computers required significant physical space due to their size and the component technologies available at the time. However, through innovation in materials, circuitry, and computing power, modern computers have become incredibly compact. This transition not only allows for personal computers on desktops but also enables the development of smartwatches and other portable devices. As a result, technological progress has made computers more accessible and integrated into daily life in various forms, illustrating the rapid pace of advancement in this field.