People have good reason to care about the

问题：

People have good reason to care about the welfare of animals. Ever since the Enlightenment, their treatment has been seen as a measure of mankind’s humanity. It is no coincidence that William Wilberforce and Sir Thomas Foxwell Buxton, two leaders of the movement to abolish the slave trade, helped found the Royal Society for the Prevention of Cruelty to Animals in the 1820s. An increasing number of people go further: mankind has a duty not to cause pain to animals that have the capacity to suffer. Both views have led people gradually to extend treatment once reserved for mankind to other species.

But when everyday lives are measured against such principles, they are fraught with contradictions. Those who would never dream of caging their cats and dogs guzzle bacon and eggs from ghastly factory farms. The abattoir and the cattle truck are secret places safely hidden from the meat-eater’s gaze and the child’s story book. Plenty of people who denounce the fur-trade (much of which is from farmed animals) quite happily wear leather (also from farmed animals).

Perhaps the inconsistency is understandable. After hundreds of years of thinking about it, people cannot agree on a system of rights for each other, so the ground is bound to get shakier still when animals are included. The trouble is that confusion and contradiction open the way to the extremist. And because scientific research is remote from most people’s lives, it is particularly vulnerable to their campaigns.

In fact, science should be the last target, wherever you draw the boundaries of animal welfare. For one thing, there is rarely an alternative to using animals in research. If there were, scientists would grasp it, because animal research is expensive and encircled by regulations. Animal research is also for a higher purpose than a full belly or an elegant outfit. The world needs new medicines and surgical procedures just as it needs the unknowable fruits of pure research.

And science is, by and large, kind to its animals. The couple of million (mainly rats and mice) that die in Britain’s laboratories are far better looked- after and far more humanely killed than the billion or so (mainly chickens ) on Britain’s farms. Indeed, if Darley Oaks makes up its loss of guinea pigs with turkeys or dairy cows, you can be fairly sure animal welfare in Britain has just taken a step backwards.

It can be inferred from the third paragraph that（）

A. the public’s ignorance of scientific research results in attacks on science

B. a measure of mankind’s humanity is taken into account

C. confusion and contradiction result from vulnerable campaigns

D. the debate is bound to aggravate in the next decade