What was electricity first used for?

The correct option highlights that electricity was primarily utilized for outdoor lighting and industrial work during its early applications. This aligns with historical developments in the late 19th century when electric power began to be harnessed for practical uses.

The emergence of electric light, such as Thomas Edison's incandescent bulb, revolutionized outdoor and street lighting, making cities safer and more functional during nighttime. At the same time, industries began to adopt electric power to enhance productivity, replacing steam and water sources with electricity for operating machinery, which enabled more efficient manufacturing processes.

While residential heating came later as electric heating technology developed, and domestic appliances like refrigerators and washing machines were introduced much later in the 20th century, the initial significant impact of electricity was indeed in outdoor and industrial settings. Telecommunications also came into play later with advancements in electric technology. Thus, those contexts didn't represent the primary use of electricity in its formative years.