Final answer:
The outbreaks of plague during the mid-14th century, which are discussed in the passage by Lisan al-Din Ibn al-Khatib, led most directly to the decline of many major cities across Eurasia due to high mortality rates and ensuing social and economic disruptions.
Step-by-step explanation:
The passage by Lisan al-Din Ibn al-Khatib speaks to the acceptance of the theory of contagion during the outbreaks of plague in the mid-14th century. Contrary to some religious explanations at the time, he argues that empirical observations support the idea of contagion, and to deny it would be harmful to the lives of the faithful. The passage you provided discusses the repercussions of the plague and the attitude towards it during the period. The outbreaks of plague described in the passage led most directly to The decline of many major cities across Eurasia. This decline occurred as a result of high mortality rates, social disruption, and economic downturn caused by the pandemic.
Contemporaneous with Ibn al-Khatib's writings, the Black Death was having devastating effects across Eurasia, influencing social structures, the economy, and the course of human history. Although some initially viewed the plague through a religious lens, the widespread devastation and observable evidence of contagion forced a change in understanding and response to the disease. Many major cities were depopulated, leading to significant economic and social changes in the affected areas.