Which of the following is an effect of pesticides on pollinators?

The effect of pesticides on pollinators, such as bees and other beneficial insects, is primarily negative, with one of the most significant outcomes being the death of pollinating insects. Pesticides can be toxic to these organisms, often affecting their nervous systems and leading to mortality. In addition to direct toxicity, exposure to certain pesticides can impair the insects' ability to navigate, forage, and reproduce, which can have broader implications for their populations and the ecosystems dependent on their pollination services.

The other options do not accurately reflect the established impacts of pesticides on pollinators. Increased pollination rates would imply a beneficial relationship that is contrary to the evidence, as pesticide exposure typically reduces the health and viability of pollinators. The idea that there is no effect at all disregards substantial research demonstrating the harmful impacts of pesticides. Lastly, stating that pesticides are harmless to crops does not consider the complex interactions within ecosystems; while pesticides may protect crops from certain pests, they often come at the cost of harming essential pollinator species, which could eventually affect crop production due to reduced pollination efficiency.