Question

this is information shared by david homer bates, an original member of the u.s. military telegraph corps, in his book lincoln in the telegraph room.
several times a day, lincoln sat down at a telegraph office desk in the white house and read through the fresh stack of incoming telegrams, which he called \lightning messages.\
as telegraph keys chattered, he peered over the shoulders of the operators who scribbled down the incoming messages converted from morse code. he visited the office nearly every night before turning in and slept there on a cot during pivotal battles.
how did the technological development referenced in this information demonstrate an evolution in leadership during the civil war?
it established the precedent for military leaders to have autonomy to make their own decisions on the battlefield.
it reduced the need for presidents to understand military tactics in order to participate in developing strategies for key battles.
it became the primary method used by generals on the battlefield to communicate orders to the troops who were fighting.
it created a way for presidents to act as \commander in chief\ and participate in real - time decision - making without being on the battlefield.

Explanation:

1. Analyze Option 1: The text shows Lincoln using telegraphs, not giving military leaders autonomy. Eliminate.
2. Analyze Option 2: Lincoln's engagement with telegraphs suggests he was involved in strategy, so this is incorrect. Eliminate.
3. Analyze Option 3: The text focuses on Lincoln (president) using telegraphs, not generals communicating to troops. Eliminate.
4. Analyze Option 4: The telegraph allowed Lincoln (president) to get real - time info and make decisions from the White House, acting as commander - in - chief without being on the battlefield. This matches the technological impact on leadership.

Answer:

D. It created a way for presidents to act as "commander in chief" and participate in real - time decision - making without being on the battlefield.