Choice A is the best answer because it most logically completes the text’s discussion of the significance of the War of 1812 in British historical memory. In this context, “tenuous” means vulnerable or uncertain. The text indicates that the War of 1812 was both smaller, and less prominent, than the conflict with France, and resulted in no significant geopolitical changes. These details imply that the War of 1812 is less likely than other British historical events to be remembered, giving the War of 1812 a tenuous place in British historical memory.
Choice B is incorrect because in this context “enduring” would mean lasting or durable, but the text describes the War of 1812 as being overshadowed by, and smaller than, the simultaneous conflict with France. This seems to conflict with the notion that the War of 1812 has an enduring place in British historical memory. Choice C is incorrect because in this context “contentious” would mean likely to cause disagreement, and while there likely are contentious issues related to the War of 1812, nothing in the text discusses or implies any such disagreement. Choice D is incorrect because in this context “conspicuous” would mean obvious, but the text describes the War of 1812 as being overshadowed by, and smaller than, the simultaneous conflict with France. Rather than suggesting that the War of 1812 has a conspicuous place in British historical memory, these descriptions suggest that its place is not particularly obvious.