Which of the following is an inference? a burning candle is extinguished when it is covered with a jar. the candle burns longer than expected in a jar that has a plant in it. a plant lives longer than expected in a jar that has a burning candle. there is more oxygen in the jar because there is a plant in it.

The correct answer is option D, There is more oxygen in the jar because there is a plant in it.

Explanation:

An inference is a conclusion derived on the basis of observation from instances. Like in this case the researcher observed that when a candle is burned inside a jar with a plant, the candle burns longer than when it is burned inside a jar without a plant.  From this researcher derived the inference that since plant release oxygen during respiration,  candle was able to burn a little longer .

D: There is more oxygen in the jar because there is a plant in it.

Explanation:

In order to be capable of engaging the key elements of adaptive immunity (specificity, memory, diversity, self/nonself discrimination), antigens have to be processed and presented to immune cells. Antigen presentation is mediated by MHC class I molecules, and the class II molecules found on the surface of antigen-presenting cells (APCs) and certain other cells.

MHC class I and class II molecules are similar in function: they deliver short peptides to the cell surface allowing these peptides to be recognised by CD8+ (cytotoxic) and CD4+ (helper) T cells, respectively. The difference is that the peptides originate from different sources – endogenous, or intracellular, for MHC class I; and exogenous, or extracellular for MHC class II. There is also so called cross-presentation in which exogenous antigens can be presented by MHC class I molecules. Endogenous antigens can also be presented by MHC class II when they are degraded through autophagy.

Explanation: